/********************************************************************************
 * Copyright (c) 2015-2019 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/

package org.eclipse.mdm.api.dflt.model;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;

import org.eclipse.mdm.api.base.adapter.Core;
import org.eclipse.mdm.api.base.model.BaseEntity;
import org.eclipse.mdm.api.base.model.ContextType;
import org.eclipse.mdm.api.base.model.Deletable;
import org.eclipse.mdm.api.base.model.Describable;
import org.eclipse.mdm.api.base.model.TestStep;

/**
 * Implementation of the template test step entity type. A template test step
 * describes the composition of {@link TemplateRoot}s which in finally is a
 * template for a persisted context description ("as measured", "as ordered"). A
 * template test step implements the {@link Versionable} interface and hence has
 * a version and a state. As long as {@link #isEditable()} returns {@code
 * true} any part of that template test step is allowed to be modified. Once a
 * template test step is set to be valid ({@link #isValid()} == {@code true}) it
 * may be used to compose a {@link TemplateTest} and then is no longer allowed
 * to be modified in any way. If a valid template test step needs to be
 * modified, then a deep copy with a unique name and version combination has to
 * be created (deep copy means new instances).
 *
 * @since 1.0.0
 * @author Viktor Stoehr, Gigatronik Ingolstadt GmbH
 * @see TemplateRoot
 * @see Versionable
 */
public class TemplateTestStep extends BaseEntity implements Deletable, Describable, Versionable {

	// ======================================================================
	// Constructors
	// ======================================================================

	/**
	 * Constructor.
	 *
	 * @param core The {@link Core}.
	 */
	TemplateTestStep(Core core) {
		super(core);
	}

	// ======================================================================
	// Public methods
	// ======================================================================

	/**
	 * Returns the related {@link TemplateRoot} with given {@link ContextType} of
	 * this template test step.
	 *
	 * @param contextType Used as identifier.
	 * @return {@code Optional} is empty if a {@code TemplateRoot} of given
	 *         {@code ContextType} does not exist.
	 */
	public Optional<TemplateRoot> getTemplateRoot(ContextType contextType) {
		return Optional.ofNullable(getCore().getMutableStore().get(TemplateRoot.class, contextType));
	}

	/**
	 * Returns all available {@link TemplateRoot}s related to this template test
	 * step.
	 *
	 * @return Returns {@code List} contains up to 3 {@code TemplateRoot}s with
	 *         distinct {@link ContextType}s.
	 */
	public List<TemplateRoot> getTemplateRoots() {
		List<TemplateRoot> templateRoots = new ArrayList<>();
		getTemplateRoot(ContextType.UNITUNDERTEST).ifPresent(templateRoots::add);
		getTemplateRoot(ContextType.TESTSEQUENCE).ifPresent(templateRoots::add);
		getTemplateRoot(ContextType.TESTEQUIPMENT).ifPresent(templateRoots::add);
		return templateRoots;
	}

	/**
	 * Replaces current {@link TemplateRoot} with the given one.
	 *
	 * @param templateRoot Is not allowed to be null.
	 * @see #removeTemplateRoot(ContextType)
	 */
	public void setTemplateRoot(TemplateRoot templateRoot) {
		getCore().getMutableStore().set(templateRoot, templateRoot.getContextType());
	}

	/**
	 * Removes current {@link TemplateRoot} with given {@link ContextType}.
	 *
	 * @param contextType Used as identifier.
	 * @return Returns {@code true} if the {@code TemplateRoot} has been removed.
	 */
	public boolean removeTemplateRoot(ContextType contextType) {
		boolean contained = getTemplateRoot(contextType).isPresent();
		getCore().getMutableStore().remove(TemplateRoot.class, contextType);
		return contained;
	}

	/**
	 * Returns the {@link TemplateTestStep} the given {@link TestStep} is derived
	 * from.
	 *
	 * @param testStep The {@code TestStep} whose {@code TemplateTestStep} is
	 *                 requested.
	 * @return {@code Optional} is empty if the given {@code TestStep} is not
	 *         derived from a template.
	 */
	public static Optional<TemplateTestStep> of(TestStep testStep) {
		return Optional.ofNullable(getCore(testStep).getMutableStore().get(TemplateTestStep.class));
	}

}